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Anonymous at Tue, 9 Apr 2024 20:12:24 UTC No. 16121348

https://phys.org/news/2024-04-magnetic-levitation-material-potential-gravity.amp

Researchers at the Quantum Machines Unit at the Okinawa Institute of Science and Technology (OIST) are studying levitating materials—substances that can remain suspended in a stable position without any physical contact or mechanical support.

The most common type of levitation occurs through magnetic fields. Objects such as superconductors or diamagnetic materials (materials repelled by amagnetic field) can be made to float above magnets to develop advanced sensors for various scientific and everyday uses.

Prof. Jason Twamley, head of the unit, and his team of OIST researchers and international collaborators have designed afloating platformwithin a vacuum using graphite and magnets. Remarkably, this levitating platform operates without relying on external power sources and can assist in the development of ultra-sensitive sensors for highly precise and efficient measurements. Their results have beenpublishedin the journalApplied Physics Letters.

When an external magnetic field is applied to 'diamagnetic' materials, these materials generate a magnetic field in the opposite direction, resulting in a repulsive force—they push away from the field. Therefore, objects made of diamagnetic materials can float above strong magnetic fields. For instance, in maglev trains, powerful superconducting magnets create a strong magnetic field with diamagnetic materials to achieve levitation, seemingly defying gravity.

Graphite, the crystalline form of carbon found in pencils, is strongly repelled by magnets (highly diamagnetic). By chemically coating a powder of microscopic graphite beads with silica and mixing the coated powder in wax, the researchers formed a centimeter-sized thin square plate that hovers above magnets arranged in a grid pattern.

The graphite composite plate wiggles above the magnets for a long time but loses energy over time due to air friction.